Gone south has a pretty negative meaning, at least in my dictionary. It means being completely lost and gone without notice. The past weekend was more in the sense of “gone north” literally and figuratively. When one is nearly at the breaking point it is usually better to go somewhere and disconnect.
Now I am not ready to do anything irrational, rest assured. But being tired in a general sense is definitely applicable to me. So this weekend was a long weekend for my wife and for me.